1. Field of the Invention
The present invention relates to a sheet feeding apparatus and an image forming apparatus, and more particularly, to a structure configured to fix a sheet stacking portion suspended by a flexible member.
2. Description of the Related Art
Hitherto, there are known image forming apparatus, such as a printer, a copying machine, and a facsimile machine, which include a sheet feeding apparatus configured to feed a sheet to an image forming portion. Further, as the sheet feeding apparatus, there is known one in which sheets are stacked on a sheet stacking portion which is provided in a sheet storing portion in a manner that the sheet stacking portion can be raised and lowered, and after the sheet stacking portion is raised to a sheet feedable position, the sheet is sent toward the image forming portion by a sheet feeding portion. As such a sheet feeding apparatus, there is known one in which the sheet stacking portion is suspended by a wire. When the sheets are stacked, the wire is wound off to lower the sheet stacking portion to a predetermined sheet stacking position so as to facilitate the stacking of the sheets.
The sheet feeding apparatus includes a sheet surface sensor configured to detect a level of the uppermost sheet of sheets stacked on the sheet stacking portion. The sheet surface sensor is turned OFF when the uppermost sheet is located at a feedable level, that is, when the sheet can be fed. When the level of the uppermost sheet becomes lower than the feedable level after the sheets are sequentially fed, the sheet surface sensor is turned ON.
When the sheet surface sensor is turned ON, a control portion in turn drives a motor to rotate a winding-up drum, to thereby wind up the wire. With this, the sheet stacking portion is raised. When the level of the uppermost sheet reaches the feedable level, the sheet surface sensor is turned OFF to stop the motor and stop the sheet stacking portion. During feeding of the sheets, this operation is repeated to constantly maintain the level of the uppermost sheet within a range of a substantially constant level.
By the way, the sheet stacking portion is suspended in the sheet storing portion so that the sheet stacking portion can be raised and lowered. Therefore, for example, when the sheet stacking portion significantly swings due to vibration or impact during transportation of an image forming apparatus, the sheet stacking portion or the peripheral member thereof may be scratched or damaged. In view of this, conventionally, as disclosed in, for example, Japanese Patent Application Laid-Open No. 2007-197204, a tape, a fixing member for transportation purpose, or the like is used to fix the sheet stacking portion to the sheet storing portion, to thereby prevent the scratch and damage due to the vibration or impact during transportation.
However, in the case of the conventional sheet feeding apparatus and image forming apparatus in which the sheet stacking portion is fixed by the tape as described above, when the adhesion of the tape is weak, the tape may peel off during transportation, while when the adhesion is too strong, it is difficult to remove the tape. Further, in the case where the fixing member for transportation purpose is used, it is necessary to mount the fixing member at the time of assembly, and a user needs to remove the fixing member before use. Thus, a large amount of time and effort is required.
Further, when the user forgets to remove the tape or the fixing member before use, the sheet stacking portion is raised in a state in which the tape or the fixing member is fixed, and hence the sheet stacking portion or the peripheral member thereof may be scratched or damaged when the sheet stacking portion is raised. Further, after the fixing member is removed, if the user lifts the sheet stacking portion while the sheet stacking portion is raised to the sheet feedable position or while the sheet stacking portion is lowered from the sheet feedable position, the wire may be slacked to be disengaged, or the slack wire may be caught on a frame or the like to cause damage or the like.